1. Field of the Invention
The present invention relates to an inkjet printer, and more particularly, to a method and an apparatus to control a printing operation according to whether a fed printing sheet belongs to at least one or more kinds of user printing sheets of which kinds and feature values are registered in advance.
2. Description of the Related Art
In inkjet recording apparatuses such as printers, copiers, facsimiles, plotters, or the like, an image is recorded by dropping ink droplets discharged from a head right onto a printing sheet, and then the ink is dried through the evaporation in the air or through permeation into the printing sheet. Due to the above recording methods, the characteristics of a printing surface of the printing sheet affect the image quality of a printed material.
Accordingly, before starting a printing operation, in a user interface, a user can select one of an inkjet sheet mode, in which printing is performed on a coated sheet having a coat film capable of increasing the permeability of ink or a glossy sheet, and a general sheet mode, in which printing is performed on a general sheet not having a coat film. A printer controller controls a printer engine according to the selected sheet mode.
Meanwhile, an optical sensor is attached to a predetermined position of a feed tray. A firmware of the printer controller identifies the kind of a printing sheet fed into the feed tray based on light reflected from the fed printing sheet and the kind of a registered sheet from an identification table which defines the relationship between the registered sheet and light reflected from the registered sheet. The printer controller controls the printer engines depending on the kind of a printing sheet identified by a printer.
A method of controlling the printer engine according to the kind of the printing sheet will be described. For example, since an inkjet sheet has a higher ink permeability than a general sheet, when compared with the general sheet mode, in the inkjet sheet mode, a head rapidly scans light, a large number of sheets pass, a small number of nozzles are used at a time, and the volume of ink droplets is small.
However, the inkjet sheet mode and the general sheet mode vary according to the kind of inkjet recording apparatuses. Also, the printing sheet is made of different materials or light is reflected differently according to a position of the feed tray in which the optical sensor is installed and manufactured. Thus, errors may occur when the printer controller identifies the kinds of printing sheets.